PHIL 1290 Critical thinking assignment

PHIL 1290 – ASSIGNMENT 5

Wednesday, April 5, 2017

INSTRUCTIONS

Answer all 5 questions. Your completed Assignment 5 must be typed and submitted (hard copy) at the start of class on Friday April 21st. Submissions by Email will not be accepted without a documented medical excuse.

This assignment is worth 20% of your final course grade. It will be graded out of 20.

Question #1. For each of the following three inferences, state whether the conclusion is deductively valid or deductively invalid. (Worth 1.5 marks)

Inference (a)

1: Some cats are not pests.

2: All cats are pets.

3: Thus, not all pets are pests.

Inference (b)

1: It is false to say that no political science professors are money-grubbers.

2: No socialists are money-grubbers.

3: So, it is not true that all professors of political science are socialists.

Inference (c)

1: Not all pigs are winged animals.

2. All winged animals can fly.

3: Therefore, some pigs cannot fly.

Question #2. For the following sorites, state the hidden conclusions and indicate whether the main conclusion is deductively valid or invalid. (Worth 1.5 marks)

1. All dogs are mammals.

2. No reptiles are mammals.

3. All snakes are reptiles.

4. All cobras are snakes.

5. So, no dogs are cobras.

Question #3. Evaluate the following argument. In your evaluation you should address whether each premise is acceptable or unacceptable, providing the condition of premise acceptability/unacceptability, indicate the nature of each inference (deductive or inductive), and whether or not each inference is a strong argument. (Worth 5 marks)

1. The complex material dealt with at university requires that students be well grounded in basic skills of reading and writing.

2. According to many educators, elementary school teachers teach students in their most formative years when basic skills are best taught.

3. Therefore, the job of elementary school teachers is more important than that of university professors.

4. People should be paid according to the importance of their jobs to society.

5. University professors are already overpaid.

6. Elementary school teachers should be better paid than university professors.

Question #4. The text box that follows contains an ‘inference to the best explanation’ argument. The facts are drawn from the manslaughter case of R. v. John (1970) 2 C.C.C. (2d) 157 (S.C.C.). The arguer here is the prosecution and the arguer’s conclusion is that Mr. John murdered Graffie George; this conclusion is being offered as the best explanation of the facts presented.

Facts

1. Prior to August 18th Graffie George had been living with Mr. John for 18 months.

2. On the afternoon of August 21st Graffie George was found hiding in the bushes near her sister’s house at a reservation outside Whitehorse; she was ‘very dirty’ and her sister took her into the house where she stayed overnight.

3. On the evening of August 22nd the sister went out to play bingo at Whitehorse at 7 p.m. but Graffie George remained in the sister’s house because she was scared to go out.

4. Later on the evening of August 22nd Mr. John and his nephew Lester drove to the reserve where Mr. John broke into the sister’s house through a window.

5. Mr. John and Graffie George then left the sister’s house through the broken window.

6. Mr. John sent Lester on an errand after leaving the house; when Lester returned to the sister’s house Mr. John and Graffie George were gone.

7. Lester testified that on September 1st Mr. John called at the house where he was staying and told him that ‘the girl was finished,’ that ‘he did not know what he should do’ and that he ‘did not know if he should turn himself in or not.’

8. On September 14th, after being questioned concerning the whereabouts of Graffie George, Mr. John led three police officers to a place in the bushes off the Alaska Highway where Graffie George’s body was found wrapped in a blanket inside a canvass covering and trussed up with a rope.

9. The canvass covering in which the body was found was identified as a tent which, with a mattress and two blankets, had been stolen from a camp-site set up by two boys not far from a camp that had been occupied by Mr. John.

10. The pathologist Dr. Morrow, who conducted the autopsy on Graffie George, found that the cause of death was a subdural haemorrhage caused by a blunt type of force and covering the left side of the brain which had been pushed downward by the pressure of the haemorrhage; there was also bruising on George’s chest wall and abdomen consistent with blows from a fist.

11. Dr. Morrow conceded on cross-examination that the fatal injury could also be caused by a person striking their head while getting out of a car and that the other injuries could be consistent with having fallen on an object.

Explanation of the Facts: Mr. John killed Graffie George

Assume that the facts are all relevant and acceptable and assess whether the prosecution’s conclusion is inductively valid (i.e. probable given the evidence) as an IBE argument. Your answer should refer to the premises and explain why you believe that, taken together, they do or do not render the prosecutor’s explanation probable; i.e. explain the weight that you are giving the evidence and why. [Note that ‘probable given the evidence’ is much weaker than the ‘beyond a reasonable doubt’ burden of proof]

(Worth 6 marks)

Question #5. On Tuesday December 15, 2015 a televised debate was held on foreign and security affairs for the leading Republican candidates running for their party’s nomination for the 2016 Presidential election. The moderator Hewitt asked the following question of Donald Trump:

“Mr. Trump, Dr. Carson just referenced the single most important job of the president, the command, the control and the care of our nuclear forces. And he mentioned the triad. The B-52s are older than I am. The missiles are old. The submarines are aging out. It's an executive order. It's a commander-in-chief decision. What's your priority among our nuclear triad?”

Trump ‘answered’ the question as follows:

“Well, first of all, I think we need somebody absolutely that we can trust, who is totally responsible, who really knows what he or she is doing. That is so powerful and so important. And one of the things that I'm frankly most proud of is that in 2003, 2004, I was totally against going into Iraq because you're going to destabilize the Middle East. I called it. I called it very strongly. And it was very important. But we have to be extremely vigilant and extremely careful when it comes to nuclear. Nuclear changes the whole ballgame. Frankly, I would have said get out of Syria; get out – if we didn't have the power of weaponry today. The power is so massive that we can't just leave areas that 50 years ago or 75 years ago we wouldn't care. It was hand-to-hand combat. The biggest problem this world has today is not President Obama with global warming, which is inconceivable, this is what he's saying. The biggest problem we have is nuclear – nuclear proliferation and having some maniac, having some madman go out and get a nuclear weapon. That's in my opinion, that is the single biggest problem that our country faces right now.”

Hewitt tried asking the question again:

“Of the three legs of the triad, though, do you have a priority? I want to go to Sen. Rubio after that and ask him.”

Trump: “I think – I think, for me, nuclear is just the power, the devastation is very important to me.”

The moderator was, of course, asking Trump to explain and defend his policy position with respect to replacing America’s aging nuclear triad. For this assignment you are going to do what Donald Trump did not do: answer the question asked (and hopefully your answer will demonstrate what the now President Trump’s answer failed to demonstrate: that there is something functioning between your ears).

Specifically you will do the following:

i. State what is meant by the nuclear triad. (Worth ½ mark)

ii. Adopt a policy position on the replacement of the triad and state that position (worth ½ mark). Options are:

1. Replace none of the three elements (i.e. unilateral disarmament)

2. Replace all of the three elements

3. Replace some but not all of the elements (in this case state which elements you would replace)

iii. A good inductive argument for a policy position is deeply fact sensitive; remember that this is an evidential sense of validity. The arguer must present facts that are positively relevant to the conclusion and which have high probative value (i.e. taken together, the conclusion is probable given the facts provided as premises). You provide one fact that is positively relevant to your policy position that you believe has high probative value in favor of your policy position. You will explain why you believe that this fact has high probative value. (Worth 5 marks)